WO 01/86121 A1 discloses a method for cooling a shaft in a high-pressure expansion section of a steam turbine. A steam generator is provided to produce live steam with a temperature and a pressure that is higher and lower, respectively, than cooling steam that is removed from the steam generator for cooling the shaft. A high pressure expansion section is provided with a feed for the cooling steam.
Japanese Patent Application Publication 9-250306 discloses that steam bred from an intermediate stage of a boiler is mixed with high pressure initial stage nozzle outlet leak steam to prevent lowering of material force of an intermediate pressure initial stage bucket stud part.